SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7c9b316a8fa2558379e9a1e770a201df5f09d3eca6fe0fc8b0823a4fb0b6d26' 
  AND token = '8CSUJ3gzSvkTd8g5Gpp4eQtRdSXHbLY+YpnOYVeaiMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables